(Photo : REUTERS/Brendan McDermid) The Federal Government declared dolphin deaths an "Unsual Mortality Event" that must be further investigated.

In another sign of it not being safe to go in the water, a frighteningly large number of dolphins have washed up along the East Coast-dead.

While the bodies of the dead animals pose no current risk to humans, whatever is killing them may. "When you're seeing a large number of animals stranding for an unknown reason, it's telling us there's something funky going on in the environment and in the water," NOAA Fisheries public affairs officer Maggie Mooney-Seus reportedly said to the media. "Something's not right."

According to the National Oceanic and Atmospheric Administration (NOAA 91 dead dolphins have washed up in New York, New Jersey, Maryland, Delaware and Virginia in July alone. Last year, those same states had a combined death toll of nine. In 2011, the total was 16.

The cause of the massive die off remains unknown.

Environmental experts believe their could be a variety of possible factors in play, from pollution, interaction with fishing gear and diseases.

Experts have said their main worry is the potential health hazard to humans.

"Regardless of whether it's healthy, dead or sick, people need to stay away from them. These are wild animals," Mooney-Seus reportedly said. "They can bite and they can transmit diseases to human. It's always wise for people to keep a safe distance."

She added that it's against the law to approach marine animals.

A handful of the dolphins have bronchial pneumonia and at least one was carrying morbillivirus, which would be the human equivalent of chicken pox However, the majority of dolphins have yet to be tested.

A similar spike occurred in 1987 when more than 700 dolphins died and a bacterial infection was identified as the main culprit.